Characteristics of Municipal Solid Waste Composting and Determination of Composting Maturation

The characteristics of thermophilic aerobic composting process for municipal solid waste were studied. The changes of pH and organic matter content, the infrared spectra of organic matter before and after composting, the development of humification, and the toxicity for the seed were investigated. The results indicated that: the pH quickly increased and then decreased, stabilized in the neutral range; organic matter degradation occurred mainly in the first 30 days of high temperature rapid composting stage, indicating the high temperature phase played the main role in the organic matter degradation; the increases of humus, fulvic acid, humic acid and humic acid/fulvic acid ratio also showed the conversion of organic matters to humus. Composting decreased the matters inhibiting seed germination and weakened the toxicity for the plant, and the sample reached maturity through composting.

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Process modeling of municipal solid waste compost ash for reactive red 198 dye adsorption from wastewater using data driven approaches

Scientific Reports ◽

10.1038/s41598-021-90914-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Mohammad Hadi Dehghani ◽

Mehdi Salari ◽

Rama Rao Karri ◽

Farshad Hamidi ◽

Roghayeh Bahadori

Keyword(s):

Organic Matter ◽

Municipal Solid Waste ◽

Solid Waste ◽

Adsorption Process ◽

Operating Time ◽

Organic Matter Content ◽

Order Kinetic ◽

Box Behnken Design ◽

Reactive Red 198 ◽

Msw Compost

AbstractIn the present study, reactive red 198 (RR198) dye removal from aqueous solutions by adsorption using municipal solid waste (MSW) compost ash was investigated in batch mode. SEM, XRF, XRD, and BET/BJH analyses were used to characterize MSW compost ash. CNHS and organic matter content analyses showed a low percentage of carbon and organic matter to be incorporated in MSW compost ash. The design of adsorption experiments was performed by Box–Behnken design (BBD), and process variables were modeled and optimized using Box–Behnken design-response surface methodology (BBD-RSM) and genetic algorithm-artificial neural network (GA-ANN). BBD-RSM approach disclosed that a quadratic polynomial model fitted well to the experimental data (F-value = 94.596 and R2 = 0.9436), and ANN suggested a three-layer model with test-R2 = 0.9832, the structure of 4-8-1, and learning algorithm type of Levenberg–Marquardt backpropagation. The same optimization results were suggested by BBD-RSM and GA-ANN approaches so that the optimum conditions for RR198 absorption was observed at pH = 3, operating time = 80 min, RR198 = 20 mg L−1 and MSW compost ash dosage = 2 g L−1. The adsorption behavior was appropriately described by Freundlich isotherm, pseudo-second-order kinetic model. Further, the data were found to be better described with the nonlinear when compared to the linear form of these equations. Also, the thermodynamic study revealed the spontaneous and exothermic nature of the adsorption process. In relation to the reuse, a 12.1% reduction in the adsorption efficiency was seen after five successive cycles. The present study showed that MSW compost ash as an economical, reusable, and efficient adsorbent would be desirable for application in the adsorption process to dye wastewater treatment, and both BBD-RSM and GA-ANN approaches are highly potential methods in adsorption modeling and optimization study of the adsorption process. The present work also provides preliminary information, which is helpful for developing the adsorption process on an industrial scale.

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The Effect of Organic Matter Content and Turning Cycle on Municipal Solid Waste Windrow Composting

Journal of Civil Engineering Research and Practice ◽

10.4314/jcerp.v2i2.29143 ◽

2006 ◽

Vol 2 (2) ◽

Author(s):

A. O. Mayabi

Keyword(s):

Organic Matter ◽

Municipal Solid Waste ◽

Solid Waste ◽

Organic Matter Content ◽

Matter Content ◽

Windrow Composting

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Characteristics of fouling due to clay-organic substances in potable water treatment by ultrafiltration

Water Science & Technology ◽

10.2166/wst.1996.0201 ◽

1996 ◽

Vol 34 (9) ◽

pp. 157-164 ◽

Cited By ~ 2

Author(s):

Kim C.-H. ◽

M. Hosomi ◽

A. Murakami ◽

M. Okada

Keyword(s):

Molecular Weight ◽

Organic Matter ◽

Humic Acid ◽

Fulvic Acid ◽

Size Distribution ◽

Ultrafiltration Membrane ◽

Organic Substances ◽

Decomposition Products ◽

Microbial Decomposition ◽

Fouling Materials

Effects of clay on fouling due to organic substances and clay were evaluated by model fouling materials and kaolin. Model fouling materials selected were protein, polysaccharide, fulvic acid, humic acid and algogenic matter (EOM:ectracellular organic matter, microbial decomposition products) and kaolin was selected as the clay material. Polysulfone membrane (MWCO(Molecular Weight Cut-Off) 10,000, 50,000 and 200,000) was used as an ultrafiltration membrane. In particular, the flux measurement of solutions containing algogenic matter used an ultrafiltration membrane of MWCO 50,000. The flux of protein and polysaccharide with coexistence of kaolin increased in the case of the ratio of MW/MWCO being greater than one, but did not increase in the case of the MW/MWCO ratio being below one. In contrast, the flux of fulvic acid and humic acid with coextence of kaolin decreased regardless of the ratio of MW/MWCO. The addition of dispersion agent and coagulant in the organic substances and kaolin mixture solution changed the size distribution of kaolin, and resulted in a change of the flux. EOM and microbial decomposition products decreased with the increase of the fraction of organic matter having molecular weight more than MWCO of membrane. The flux of the algogenic organic matter with coexistence of kaolin decreased with the increase of the amount of kaolin. It was suggested that the decline of the flux with coexistence of kaolin was due to the change of the resistance of the kaolin cake layer corresponding to the change in kaolin size distribution with charge.

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An Experimental Study on the Melting Solidification of Municipal Solid Waste Incineration Fly Ash

Sustainability ◽

10.3390/su13020535 ◽

2021 ◽

Vol 13 (2) ◽

pp. 535

Author(s):

Jing Gao ◽

Tao Wang ◽

Jie Zhao ◽

Xiaoying Hu ◽

Changqing Dong

Keyword(s):

Heavy Metals ◽

High Temperature ◽

Fly Ash ◽

Municipal Solid Waste ◽

Solid Waste ◽

Liquid Slag ◽

Melting Process ◽

Waste Incineration ◽

Municipal Solid Waste Incineration ◽

Mswi Fly Ash

Melting solidification experiments of municipal solid waste incineration (MSWI) fly ash were carried out in a high-temperature tube furnace device. An ash fusion temperature (AFT) test, atomic absorption spectroscopy (AAS), scanning electron microscope (SEM), and X-ray diffraction (XRD) were applied in order to gain insight into the ash fusibility, the transformation during the melting process, and the leaching behavior of heavy metals in slag. The results showed that oxide minerals transformed into gehlenite as temperature increased. When the temperature increased to 1300 °C, 89 °C higher than the flow temperature (FT), all of the crystals transformed into molten slag. When the heating temperatures were higher than the FT, the volatilization of the Pb, Cd, Zn, and Cu decreased, which may have been influenced by the formation of liquid slag. In addition, the formation of liquid slag at a high temperature also improved the stability of heavy metals in heated slag.

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Comparison of the mineralogical effects of an experimental forest fire on a goethite/ferrihydrite soil with a topsoil that contains hematite, maghemite and goethite

Clay Minerals ◽

10.1180/claymin.2009.044.2.239 ◽

2009 ◽

Vol 44 (2) ◽

pp. 239-247 ◽

Cited By ~ 15

Author(s):

P. Nørnberg ◽

A. L. Vendelboe ◽

H. P. Gunnlaugsson ◽

J. P. Merrison ◽

K. Finster ◽

...

Keyword(s):

Organic Matter ◽

High Temperature ◽

Forest Fire ◽

Forest Fires ◽

Organic Matter Content ◽

Matter Content ◽

Humid Climate ◽

Fe Mineralogy ◽

Reducing Environment

AbstractA long-standing unresolved puzzle related to the Danish temperate humid climate is the presence of extended areas with large Fe contents, where goethite and ferrihydrite are present in the topsoil along with hematite and maghemite. Hematite and, particularly, maghemite would normally be interpreted as the result of high temperature as found after forest fires. However, a body of evidence argues against these sites having been exposed to fire. In an attempt to get closer to an explanation of this Fe mineralogy, an experimental forest fire was produced. The results showed a clear mineralogical zonation down to 10 cm depth. This was not observed at the natural sites, which contained a mixture of goethite/ferrihydrite, hematite and maghemite down to 20 cm depth. The experimental forest fire left charcoal and ashes at the topsoil, produced high pH and decreased organic matter content, all of which is in contrast to the natural sites. The conclusion from this work is that the mineralogy of these sites is not consistent with exposure to forest fire, but may instead result from long-term transformation in a reducing environment, possibly involving microbiology.

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